CASE REPORTS
Knee Pain in Slipped Femoral Capital Epiphysis Causing a Delay in Diagnosis S. RICHARD
KAPLAN, M.D. AND LEONARD KLINGHOFFER,
From tbe Graduate Hospital, Pbiladelpbia, Pennsylvania.
University
HE earIy clinica recognition and roentgenographic confirmation of shpped capita1 femora1 epiphysis constitute the onIy means of improving and assuring more uniform end resuIts in this disabIing afhiction of the adoIescent chiId. Once actua1 slipping has occurred, the prognosis is aIways doubtfu1 regardIess of the type of therapy, since subsequent changes in the head of the femur cannot be foretoId. One cannot, therefore, overemphasize the counseI offered by Mayer [g] in 1937, after a ten year study of sIipped femora1 epiphysis, nameIy that the aII-important factor in successfu1 treatment is earIy recognition. Any review of Iate end resuIts confirms the fact that the Iater treatment is instituted the poorer the usua1 resuIt and that earIy detection of slipping (if not the so-caIIed pre-slipping stage) permits the simpIest, satisfactory form of treatment nameIy naiIing in situ. [f,S]. SteindIer [14] beIieved that the diagnosis couId be made on the basis of hip pain and resuIting antaIgic gait. Howorth [6,7] describes the earIy symptoms as those of miId synovitis of the hip, incIuding sIight pain, Iimp, stiffness He indicated that the pain and disability. usuaIIy is slight, increasing with activity and beginning sIowIy with referra1 to the groin, front, or inner side of the thigh, or inner side of the knee aIong the course of the obturator nerve. Burrows [J] described pain and a Iimp occurring simuItaneousIy in about a haIf the IOO cases he reviewed and concIuded that pain began more often about the hip than the knee, Volume IOI. June 1961
Pennsyltania
but occasionaIIy in both. According to most authors, pain and Iimp are noted prior to the demonstration of roentgenographic changes and usuaIIy start graduaIIy, the pain most often being intermittent with exacerbations each time a change in the epiphysis-neck relationship occurs. However, in a review of fifty-seven patients with sixty-four diseased hips, CIeveIand et a1. [4] found that changes in both meta- and epiphysis antedated the stated onset of symptoms and concIuded that the beginning of symptoms generaIIy denoted actua1 occurrence of considerabIe further sIipping. WhiIe it is beyond the intended scope of this paper to discuss the roentgenographic diagnosis of the disease, we beIieve it worthwhiIe to point out the contribution of Pomeranz and Sloane [I?] who in 1934 reviewed IOI examples of epiphysioIysis and Iater coIIected records of 300 additiona cases. Pomeranz gave an exceIIent description [12] of early roentgenographic criteria and wrote that it was startIing to find so IittIe in textbooks of radioIogy on the earIy recognition of this disease which produces such deformity and disabiIity and was so commonIy overIooked. AIthough knee pain in association with sIipped capita1 femoral epiphysis is mentioned by most authors in their discussion of diagnosis, we beIieve it has been given inadequate emphasis. More than thirty years ago, WiIIis [r~] in a report of fifteen cases of sIipped femora1 epiphysis, Iisted two case histories in which the patient presented with knee pain. More recentIy, Burrows [3], in his Iist of causes of deIay in treatment, recorded three cases of diagnostic faiIure because of attention directed
of Pennsylvania,
T
American Journal of Surgery.
M.D., Philadelphia,
798
DeIayed
Diagnosis
of Slipped
FemoraI
Sartariu
Epiphysis
Ix...
Obturator Muscular
bra.
Femoral
II..
.__
Adductorbrevis
Articular knee
br. to joint.
FIG. I. Diagrammatic
_...Infrapatellar _ _ _ S aphenoua
br. n.
distribution of obturator nerve.
to the knee to the excIusion of the hip for five, ten and tweIve months, respectiveIy. The discussion by PhiIip D. WiIson folIowing the oresentation of a paper on disolacement of the npper femora1 epi’physis by Badgley [I] in 1928, was of great interest to us. He stated that, in his experience, the pain is referred to the knee in the beginning of aImost a11 cases. Most recently, NichoIson and QuaIIs [II] pointed out that the referra1 of pain in sIipped femoral eoiohvsis is usuallv to the knee. Referred barn is an old problem and although several theories attempt to expIain it, none-is entireIy satisfactory. Referral is aIways to the somatic segments whose sensorv nerves terminate in the same soinal cord levels that receive the sensory fibers-of the area responsibIe. AIthough the exact site of transfer of impulses within the centra1 nervous svstem is not cIear. the peripheral pathways are usuaIIy we11 known. The nerves of the hip joint are mostIy derived from the lumbar pIexus. They are: (I) ~ , a median skin branch from the femora1 nerve and (2) the obturator nerve, which through its anterior branch suppIies the anterior and median part of the capsuIe and through other branches supplies the intraarticular Iigament and acetabuIum. Other nerves reach the hip joint, either by way of the Nervus ischiaticus or Ouadratus femoris from the sacral pIexus. The accessory obturator, when present, aIso sends a twig to the hip ioint. Of the two terminal branches of the anterior division of the obturator nerve, one is distributed to the femoral artery, and the L/
Y
799
FIG. 2. Diagrammatic
distribution of femoral nerve.
other, a cutaneous branch, communicates with the subsartoria1 pIexus. The subsartorial branch is occasionaIIy longer than usua1 and it descends aIong the dorsa1 border of the sartorius to the media1 side of the knee. Twigs join it with the saphenous nerve, a cutaneous branch of the femora1 nerve [2,10]. (Figs. I and 2.) AIthough true referred or reflex pain in the knee probabIy does occur, a good dea1 of this pain is undoubtedIy pureIy periphera1 and shouId more appropriateIy be caIIed radiating pain. In inff ammatory hip disease it is probable that pain propagated to the knee arises through suffusion into the obturator nerve which runs in the immediate neighborhood of the joint. In this case, there would be no reflex arc of referra1 since pain perceived at the knee wouId mereIy be the result of irritation of the proxima1 obturator nerve at the hip joint. We beIieve that knee pain in sIipping of the capita1 femora1 epiphysis is due to a combination of both these mechanisms. When there is a true reflex arc, the impuIse is probabIy carried proximally to the centra1 nervous system by way of the obturator branch which accompanies the Iigamentum teres; the other Iimb of the reflex arc is apparentty via the obturator branches which suppIy the upper haIf of the knee joint and median side of the thigh as described previously. (Fig. 3.) We have had occasion to treat two chiIdren in whom the diagnosis of slipped capita1 femora1 epiphysis was missed for periods of
KapIan
.-Reflex
and
Klinghoffer
pain FIG. 4. CASE I. Roentgenograms of the knee prompting diagnosis of Osgood-Schlatter disease.
FIG. 3. The reffex arc in referred pain from hip to the knee.
two years and one year, respectiveIy. Their onIy presenting compIaint was knee pain which was thought due entirely to concomitant disease in the knee. The simuItaneous occurrence of disease in both areas, one obscuring the other, is in our opinion worthy of presentation since only by awareness of such situations can deIays in diagnosis be avoided. This may serve to stress the fact that knee pain aIone may be the heraIding symptom of sIipped femora1 epiphysis. Even in the presence of knee pathology, therefore, the hip shouId aIways be considered and examined in patients with knee pain.
The patient stood with the right foot externally rotated and in slight equinus. There was a positive right Trendelenburg sign. The right hemi-pelvis was slightly lower than the Ieft. In the supine position, the right leg was found to be shortened by ?/a inch and externaIIy rotated. The right hip was limited in a11 motion particularly interna rotation and flexion. The knee appeared norma except for some prominence of the tibia1 tubercIe. There was I inch of atrophy of the right thigh and 34 inch atrophy of the right calf. Roentgenograms of the right hip reveaIed, as expected, a marked degree of sIipping of the capita1 epiphysis. (Fig. 5A.) The patient was immediately admitted to the hospita1 and underwent wedge osteotomy of the right femoral neck. (Fig. 5B.) CASE II. When first seen, J. B. C. was a thirteen year oId boy who had symptoms dating back one year. He had sustained a footbaI1 injury which left him with some residual intermittent pain in the left knee. This eventualIy stopped but a Iimp persisted and after two months he was taken to his family physician. A clinica diagnosis of OsgoodSchlatter disease was made and confrrmed by roentgenograms of the knees. Treatment consisted of a regimen of moderateIy restricted activities. Because of a shortening of the Ieft Iower extremity, a heel Iift was prescribed for the left shoe. With this, he was aIlowed fuI1 weight bearing. He had no other known therapy for about eight months, when, because of continued symptoms in the Ieft knee, a cast was appIied and worn for seven weeks. When the cast was removed, the Iimp was remarkabIy improved and he was aIIowed increasing activity. Two weeks Iater, whiIe riding his bicycIe, he suddenIy feIt stiff and strange in the Ieft hip and fell off. This was followed by severa days of pain in the Ieft hip which graduaIIy disappeared; however, Iimited motion of hip joint persisted and the Iimp returned. Orthopedic consultation was ob-
CASE REPORTS CASE I. When first seen by us, J. S. was a sixteen year oId boy who had symptoms dating back two years. He told of the gradua1 onset of sharp stabbing pain on the media1 aspect of the right knee without any history of trauma. The pain occurred without specific reIation to activity or position. Six months after onset, as the pain increased and caused him to Iimp, he consuIted his famiIy physician. The knee was x-rayed (Fig. 4) and the diagnosis of Osgood-Schlatter disease was made. He was treated with diathermy with relief for six months. At that time, the pain in the knee recurred and was accompanied by a feeIing of weakness and giving way in that joint. He was therefore given a knee brace and rehef was obtained again for about six months. When seen by us, he compIained of pain and weakness despite constant wearing of the brace.
800
DeIayed
Diagnosis
of SIipped
FemoraI
Epiphysis
FIG. 5. CASE I. A, initial roentgenogram of the hips. Note the convexity on the dorsum of the neck of the right femur as compared with the reIative concavity on the Ieft side. B, postoperative fiIms demonstrating restoration of normal reIationship between the head and neck of the right femur following wedge osteotomy.
FIG. 6. CASE II. A, initia1 anteroposterior view of the Ieft hip showing marked displacement of the femora1 head and an even more prominent dorsa1 convexity of the neck than was seen in Case 1. B, initia1 IateraI view demonstrating aImost compIete posterior slip of the femora1 head. This cannot be appreciated in the anteroposterior view. C, postoperative anteroposterior Hm with norma head-neck reIationship foIlowing wedge osteotomy. D, IateraI view foIIowing osteotomy of the femora1 neck and fixation with a Smith-Peterson nai1. 801
KapIan
and KIinghoffer
tained and the foIIowing cIinica1 findings were noted. The patient walked with a Iimp of the left Iower extremity, showed a positive left TrendeIenburg sign, Iimited motion of the Ieft hip, and a >$ inch shortening of the Ieft leg. The range of motion in the left hip Iacked go degrees of flexion as compared with the opposite side. Adduction was fuI1 in range but abduction was moderateIy Iimited and the Ieft hip couId not be internaIIy rotated even to the midline. Roentgenograms reveaIed (Fig. 6A and B) a marked sIipping of the left capita1 epiphysis with head and neck changes indicative of Iong-standing increasing deformity. After preIiminary traction, wedge osteotomy was required to restore the headneck reIationship. (Fig. 6C and D.) SUMMARY
Two cases of unilatera1 slipped femora1 epiphysis are presented in which the diagnosis was missed for periods of two years and one year, respectivety, because of failure to recognize the significance of knee pain as a possibIe symptom of hip disease. These cases were compIicated by added factors of knee disease in the same extremity, namely, osteochondritis of the tibia1 tubercle. By the time these conditions were recognized, it was aIready too Iate for the simpIer types of therapy with the prospect of favorabIe outcome. It is emphasized that the occurrence of such disease in the knee shouId not precIude examination of the hip since part or even a11 of the symptoms in the knee may reflect disease of the hip. The anatomy of radiation of pain from the hip to the knee is reviewed and an attempt made to stress the frequency with which this condition causes knee pain as one of its major compIaints.
REFERENCES
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2.
3. 4.
BADGLEY, C. E. Displacement of the upper femora1 epiphysis, summary of 27 studied cases. J. A. M. A., 92: 355, rg2g. BEHAN, R. J. Pain, its Origin, Conduction Perception and Diagnostic Significance, p. 240. New York and London, 1922. D. AppIeton ti Co. BURROWS, H. J. Slipped upper femoraI epiphysis. J. Bone &+Joint &rg., 39-B: 641, 1957.. CLEVELAND. , M.. , BOSWORTH. D. M., DALY. S. N. and HESS, W. E. Study of dis&aced -capita1 femora1 epiphysis. J. Bone Ed Joint Surg., 33A:
95% ‘951. HOWORTH, B. Slipping of the upper femora1 epiphgsis. J. Bone c~ Joint Surg., 31-A: 734, 1949. HO&IR~H, B. Textbook of Orthopedics, pp. 6go71 I. PhiIadeIohia. 1042. W. B. Saunders Co. HOWORTH, B.’ Slippi& of the upper femoral epiphysjs. Clin. h&o;., IO: 148, 1&7. KLEIN. A.. JOPLIN. R. J.. REIDY. J. A. and HANELIN, J. SIipped capital femoraI epiphysis; early diagnosis and treatment faciIitated by “normal” roentgenograms. J. Bone 0 Joint Surg., 34-A: 233, 1952. 9. MAYER, L. The importance of earIy diagnosis in the treatment of sIipping femora1 epiphysis. J. Bone TVJoint Surg., Ig: 1046, 1937. IO. MORRIS, H. Human Anatomv, 10th ed., PP. I 123I 129.. Edited by Schaeffe;; J. Pars&i, PhiIadeIphia, 1942. BIakiston Co. NICHOLSON, J. T. and QUALLS, D. M. Early evaluII. ation of muscuIo-skeIeta1 Iesions by the pediatrician. Pediat. Clin. Nortb America, 6: 1163, ‘959. POMERANZ, M. M. EpiphysioIysis or separation of the capita1 epiphysis of the femur in adoIescence. Am. .f. Roentgenol., 40: 580, 1938. 13. POMERANZ. M. M. and SLOANE, M. F. SIipping of the proximal femora1 epiphysis; therapeutic-res&s in IOI cases. Arch. Surg., 30: 607, 1935. 14. STEINDLER, A. Lectures on the Interpretation of Practice, pp. 539541. Pain in Orthopedic Springtield, III., 1959. CharIes C Thomas. 15. WILLIS, T. A. The sIipping femoral epiphysis. J. Bone @ Joint Surg., I I : 779, 1929. 12.